Owoeye Accomodation 6 questions (2hr lecture)

Question 1

Automatic adjustment of the refractive state to maintain a focused retinal image. Occurs when responding to blur

Answer 1

Reflex Accommodation

Question 2

This is the change in accommodation induced during fusional vergences. Leads to Convergence accommodation/convergence ratio (CA/C)

Answer 2

Vergence Accommodation

Question 3

The refocusing that occurs due to the apparent (or perceived) nearness (proximity) of a target. Stimulated by targets located within 3 meters of an individual.

Answer 3

Proximal Accommodation

Question 4

Lead of accommodation (SHE WILL MORE THAN LIKELY ASK US THIS)

Answer 4

Tonic Accomodation

Question 5

What accommodation reduces with age?

Answer 5

Tonic Accommodation

Question 6

What factors affect accommodation?

Answer 6

Blur
Convergence
Proximal issues
Pharmacology
Minus Lens
Diseases

Question 7

What are the 3 retinal image factors:

Answer 7

Contrast, Spatial frequency, retinal image motion

Question 8

What are the 4 non retinal factors:

Answer 8

mood, voluntary effort, target luminance (brighter increases accommodation), training (vision therapy)

Question 9

If i put a minus lens in front of anyone what will it do to the patients accommodation? What about a plus lens?

Answer 9

Minus lens makes the patient accommodate.

Plus lens the patient will not accommodate.

Question 10

What are the 4 optical cues:

Answer 10

offer information about directionality (direction of image on retina, astigmatism is skewing accomodation), astigmatism, abberations

Question 11

What are the 4 non-optical cues:

Answer 11

Size, Proximity (close up everything wants to kick in), apparent distance, depth cues

Question 12

True/False: Contrast, spatial frequency and luminance factors have significant effects on accommodation.

Answer 12

False, have minimal accommodative error with these factors

Question 13

True/ False: Retinal eccentricity, retinal-image velocity factors significantly effect accommodation.

Answer 13

True!

Question 14

_______ occurs when the peripheral rays don’t coincide with the central and on axis rays. This makes the fuzz around the vision. “Rays that hit the outside of the frisbee aren’t clear as going through center of frisbee” “Kid goes under table to read”

Answer 14

Aberration

Question 15

Variation/ small range in the image distance that is tolerable without a profound defocus.

Answer 15

Depth of Focus

Question 16

True/False: Accommodation is sympathetic innervation.

Answer 16

False… parasympathetic

Question 17

What drug has a very short half-life and should not be used to determine the cycloplegic refraction? (Lasts about 2.5 hrs.)

Answer 17

Tropicamide

Question 18

These drugs are used for dialating the eyes and taking away accommodation.

Answer 18

Tropicamide, Cyclopentolate

Atropine, Homatropine, scopolamine- lots of side effects

Question 19

_________ (drug) is effective with sufficient half-life, used frequently in peds.

Answer 19

Cyclopentolate

Question 20

Why do you need peds to be dialated longer?

Answer 20

She said it takes away accommodation and she needs to correctly measure myopia because it is prevalent in young kids.

Question 21

What is another word for dilation?

Answer 21

Mydriasis

Question 22

Other drugs that affect accommodation: 8 things

Answer 22

Alcohol, Ganglion blockers, Phenothiazides and antidepressants, CNS stimulants, Marijuana, Carbonic Anhydrase inhibitors, antihistamines, morphine

Question 23

Conditions that affect accommodation: a bunch of things…

Answer 23

Diabetes
Traumatic Brain Injury (TBI)
MS
Down SYndrome
Glaucoma
Eye trauma
Syphilis

Question 24

What is a gradual age-related irreversible loss of accommodative amplitude? What age is it likely to happen?

Answer 24

Presbyopia, 2.5 D loss per year
40-45 years old
Complete loss 50-55 yrs old

Question 25

What are the complaints from presbyopia?

Answer 25

Receded near point of accommodation
Blurred vision
Discomfort and asthenopia at near.

Question 26

Contributing factors and biochemical changes that lead to the decrease of accommodation:

Answer 26

Lens thickness and size increases
ciliary muscle remains stable
zonules become less dense

Question 27

What 3 factors do not change in presbyopia?

Answer 27

zonules still have their elasticity
Ciliary muscle still functions
motor neuronal pathway still functions

Question 28

What Accommodation is treated with proper distance correction and VT (vision therapy) Plus lens wont help

Answer 28

Accommodative excess

Question 29

What accommodation is treated with proper correction and vision therapy

Answer 29

Accommodative Infacility

Question 30

What accommodation is treated with proper distance correction and plus lens.

Answer 30

Accommodative insuficiency

Question 31

True/False: In accommodation there is convergence.

Answer 31

True

Question 32

True/False: With no accommodation there is devergence

Answer 32

True

Question 33

What are 2 ways to measure the AC/A ratio?

Answer 33

• Gradient determination

- Near-Far (or calculated) determination

Question 34

Why is gradient determination better than near far determination? (SHE SAID SHE COULD ASK US THIS)

Answer 34

At the same distance proximal accommodation is controlled.

Question 35

What is expected AC/A ratio?

Answer 35

3/1 to 5/1 or (3:1 to 5:1)

Question 36

If near phoria is 2EP through subjective and then 7 EP through -1.00 D what is the AC/A ratio? and is it normal?

Answer 36

AC/A= (7-2)/1= 5/1

Yes it is wnl of expected of (3:1 to 5:1)

Question 37

If near phoria is 2XP through subject and then 7 EP through -1.00D AC/A ratio is what? is the ratio normal?

Answer 37

AC/A= (7-(-2)/1= 9/1

Not normal

Question 38

PAtient has PD=60 mm, 2XP at distance, 10XP at near (40cm)

Answer 38

Ac/A =PD(cm) + NFD (P’near- Pdistance)(m)
AC/A= 6+ 0.4 (-10–2)
= 2.8